Description of problem:
In file included from /usr/include/mozilla-1.4.1/xpcom/nsrootidl.h:11,
from /usr/include/mozilla-1.4.1/xpcom/nsISupports.h:10,
from Source/nsIScriptableMplayerPlugin.h:10,
from Source/nsScriptablePeer.h:48,
from Source/plugin.h:47,
from Source/plugin.cpp:38:
/usr/include/mozilla-1.4.1/xpcom/nscore.h:46:28: mozilla-config.h: No
such file or directory
Version-Release number of selected component (if applicable):
mozilla-devel-1.4.1-18
How reproducible:
always
Steps to Reproduce:
1.tar xzfv mplayerplug-in-2.11.tar.gz
2. cd mplayerplug-in ; ./configure
3. make
Actual results:
make fails
Expected results:
make should exit without errors
Additional info:

The title is misleading. It should be "mplayerplug-in doesn't build".
The includes are extracted from /usr/lib/pkgconfig/mozilla-plugin.pc
by pkg-config:
$ pkg-config --cflags mozilla-plugin
-I/usr/include/mozilla-1.4.1/java -I/usr/include/mozilla-1.4.1/plugin
-I/usr/include/mozilla-1.4.1/xpcom -I/usr/include/mozilla-1.4.1/string
-I/usr/include/mozilla-1.4.1/nspr
What's missing here is -I/usr/include/mozilla-1.4.1 where
mozilla-config.h is located. It's referenced by
/usr/include/mozilla-1.4.1/xpcom/nscore.h
Either mozilla-config.h should be moved to
/usr/include/mozilla-1.4.1/xpcom or the pkg-config file that lists
/usr/include/mozilla-1.4.1/xpcom should list
/usr/include/mozilla-1.4.1 as well.